BRIGHTON, Colo. (KDVR) — A man in Brighton is thankful to be alive after deadly levels of carbon monoxide filled his home over the Thanksgiving holiday.

Carbon monoxide is known as the silent killer. That “silent killer” strikes more during cold months due to faulty heating devices, according to the Brighton Fire Rescue District.

A call from security monitoring company ADT allowed the resident to quickly get out of the home. A second call to dispatch alerted Brighton firefighters to the danger.

Firefighters said levels of carbon monoxide hit 700 ppm inside the home on the 4200 block of Pioneer Place. Those levels are lethal and potentially explosive, according to Capt. Colin Brunt with Brighton Fire Rescue District.

“If we’re definite on the cause, we’ll go and turn the gas off to that certain appliance,” Brunt explained. “If we’re not totally definite, then we can just go turn the gas off, anyway, to the whole home.”

A broken heater pipe was to blame for the dangerous levels over Thanksgiving on Pioneer Place.

Brunt said now is the time to take action to protect yourself. Make sure your appliances — especially the furnace — are well-maintained and serviced. Keep carbon monoxide detectors on all levels of the home and test them once a month. Also, just like smoke detectors, ensure adequate battery power in case the power goes out.

The most common symptoms of carbon monoxide poisoning are dizziness, headache, upset stomach, weakness, vomiting, confusion and chest pain. Hundreds of people die each year in the United Sates from carbon monoxide poisoning. Officials say roughly 50,000 people will end up in an ER due to the poisoning.